A homologous series is a family of organic compounds containing a particular characteristic group and exhibiting similar properties. For example, the compounds given below belong to the alcohol family.
CH3OH methyl alcohol (methanol)
CH3CH2CH2OH propyl alcohol (1-propanol)
CH3CH2.CH2.CH2OH butyl alcohol (1-butanol)
Characteristics of a Homologous Series
All members of a homologous series exhibit some common characteristics. They are:
All the members of a homologous series can be represented by a common general formula, as they have the same functional group. For example, alkanes can be represented by the formula CnH2n+2.
CH4 C2H6 C3H8 C4H10
Methane Ethane Propane Butane
Each member of a homologous series has a common difference of -CH2 from the next higher or lower member.
Common general methods of preparation exist for all members of the series.
All members exhibit similar chemical behavior.
An increase in molecular mass of members within a homologous series show a similar regular gradation of the physical properties, such as, physical state, melting and boiling points etc.
Homologous Series
A homologous series is a family of organic compounds containing a particular characteristic group and exhibiting similar properties. For example, the compounds given below belong to the alcohol family.
CH3OH methyl alcohol (methanol)
CH3CH2CH2OH propyl alcohol (1-propanol)
CH3CH2.CH2.CH2OH butyl alcohol (1-butanol)
Characteristics of a Homologous Series
All members of a homologous series exhibit some common characteristics. They are:- All the members of a homologous series can be represented by a common general formula, as they have the same functional group. For example, alkanes can be represented by the formula CnH2n+2.
CH4 C2H6 C3H8 C4H10Methane Ethane Propane Butane
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